Class CompactTupleSketch<S extends Summary>

java.lang.Object

org.apache.datasketches.tuple.TupleSketch<S>

org.apache.datasketches.tuple.CompactTupleSketch<S>

Type Parameters:

S - type of Summary

public final class CompactTupleSketch<S extends Summary>
extends TupleSketch<S>

CompactTupleSketches are never created directly. They are created as a result of the compact() method of an UpdatableTupleSketch or as a result of the getResult() method of a set operation like TupleUnion, TupleIntersection or TupleAnotB. CompactTupleSketch consists of a compact list (i.e. no intervening spaces) of hash values, corresponding list of Summaries, and a value for theta. The lists may or may not be ordered. CompactTupleSketch is read-only.

Method Summary

Modifier and Type	Method	Description
CompactTupleSketch<S>	compact()	Converts this TupleSketch to a CompactTupleSketch on the Java heap.
int	getCountLessThanThetaLong(long thetaLong)	Gets the number of hash values less than the given theta expressed as a long.
int	getRetainedEntries()	Returns number of retained entries
TupleSketchIterator<S>	iterator()	Returns a SketchIterator
byte[]	toByteArray()	Serialize this sketch to a byte array.

Methods inherited from class TupleSketch

createEmptySketch, getEstimate, getEstimate, getLowerBound, getLowerBound, getSummaryFactory, getTheta, getThetaLong, getUpperBound, getUpperBound, heapifySketch, heapifyUpdatableSketch, isEmpty, isEstimationMode, toString

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Details

compact

public CompactTupleSketch<S> compact()

Description copied from class: TupleSketch

Converts this TupleSketch to a CompactTupleSketch on the Java heap.

If this sketch is already in compact form this operation returns this.

Specified by:

compact in class TupleSketch<S extends Summary>

Returns:

this sketch as a CompactTupleSketch on the Java heap.

getRetainedEntries

public int getRetainedEntries()

Description copied from class: TupleSketch

Returns number of retained entries

Specified by:

getRetainedEntries in class TupleSketch<S extends Summary>

Returns:

number of retained entries

getCountLessThanThetaLong

public int getCountLessThanThetaLong(long thetaLong)

Description copied from class: TupleSketch

Gets the number of hash values less than the given theta expressed as a long.

Specified by:

getCountLessThanThetaLong in class TupleSketch<S extends Summary>

Parameters:

thetaLong - the given theta as a long in the range (zero, Long.MAX_VALUE].

Returns:

the number of hash values less than the given thetaLong.

toByteArray

public byte[] toByteArray()

Description copied from class: TupleSketch

Serialize this sketch to a byte array.

As of 3.0.0, serializing an UpdatableTupleSketch is deprecated. This capability will be removed in a future release. Serializing a CompactTupleSketch is not deprecated.

Specified by:

toByteArray in class TupleSketch<S extends Summary>

Returns:

serialized representation of this sketch.

iterator

public TupleSketchIterator<S> iterator()

Description copied from class: TupleSketch

Returns a SketchIterator

Specified by:

iterator in class TupleSketch<S extends Summary>

Returns:

a SketchIterator